hoagland



@uitrit tstrs gstent @fitte G. H. HOAGLAND. OFv PORT JERVIS, NEW YORK.

Letters .Patent No. 67,302, dated July 30, 1867.

IMPROVEMENT IN STEAM-ENGINE SLIDE-VALVES.

@te Srlgehule referrer tu im these Petters ntent mit marking par! at the same.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, G. H. HOAGLAND, of Port Jervis, in the county of Orange, and Stute of New York, have `invented a new and useful Improvement on Balance Slide-Valves; and I do hereby declare that the fol `lowing is a full, clear, and exact description of the construction audperation of the saule, reference being had to the annexed drawing making a part of this specitication, in whichn Figure 1 represents a transverse section of the steam-chest of an engine cylinder, with my improved slidevalve therein. l i

Figure 2 a longitudinal section of the same, and

Figure 3 a rear view or horizontal section thereof, with the steam-chest cover removed.

The nature of my invention consists in a novel combination of V-shaped slide-valve, box, or case thereto, with its parts or passages also open at its ends, the whole being arranged within a steam-chest, substantially as hereinafter described; and'said invention further consists in a combination with the valve-box of certain relief or safety-valves, controlling openings that establish communication between the steamports and interior of the steam-chest, for the purpose of preventing damage or breakage to the cngine-cylinder, or other uorking parts.

In the accompanying drawing, the outer box or case there represented is the steamchest of an enginecylinder. E is theexhaust port, and Sl S2 are the steam passages through the bottom plate K of the valvebox D, arranged within said case, which passages are in communication with corresponding passages or extensions thereof through the portion of the engine-cylinder on which the said box or its steam-chest A is seated. The cover F of this box D is represented as a loose plate which is kept close down to the sides of the box D by screws b that may be arranged to pass through the top cover of the steam-chest, and also be extended so as to keep down the box'D to the steam-chest face. The box D is open at both ends, a V-shaped way or passage being established throughout its length for the accommodation of the valve of similar configuration, se far as its end faces O and O2 are concerned, which are connected by a tube,P, and bars Gl and G2, all of which maybe cast together. R is the valve stem, ran through the centre of the tube P, and suitably secured thereto. The passages E S1 S2 extend upwardly within the box D, as far as the cover F, or nearly so, the steam passages S1 S2 communicating by lateral openings pip, in said box, with the interior of the steam-chest A. The steam has a free passage between the sides of the steam-chest and the box D, from one end of` said chest to the other. The steam can only enter the steam-ports of the engine-cylinder, or pass from the steam-chest thereto, past or outside the ends ofthe valve as it is reciprocated within the box D, the ends of which are open for ingress of the steam, such action of the valve alternately establishing steam communication from opposite ends of the valve with the ports Sl S, and the latter alternately communicating through the recessed or middle portion of thel valve with the exhaust passage ofthe cylinder. The upper portion or face of the vulve is provided with a packing, H, which may be of rectangular form, and is seated within a groove made in said face, resting on springs g therein, and being forced up or against the inside face of the cover F, said packing being a suicient distance from the outer edges of the upper face of the valve to allow of steam acting on a sudicient area. of the latter to counteract the pressure of steam on the undcr'portion or shelving sides of the blocks O1 O2, as they alternately pass over the stationary ports or passages to which steam has been admitted. 'lhis construction serves to give to the valve a bala-nce character, keep it close to its seat, and prevents leakage of steam to the exhaust. Though here described as of a V-form, it is preferred to square oli` the bottom and side edges of the valve, as represented, to prevent cutting on its seat, and for the accommodation of the packing. It is essential, however, that its general contour should be that of a V, as such is found to wear better tha-n a circular or other form, and the wear of thesame be provided for by adjustment of the loose cap or cover F. The openings ppz, made in the Vone side of valve-box D, and establishing communication between the steam-ports S S2 and interior of the steam-chest, are covered by valves N1 N2, hung to open outwards, and shut'by their own weight and the pressure of the steam in the chest. These valves act as safety or relief valves in case of the pressure of the steam in the cylinder or the ports exceeding that ot' the steam in the chest, sometimes occurs in locomotive engines on giving counter-steam; they also serve to facilitate the expulsion of Water from the cylinder or ports. As soon as the requisite relief, however, is afforded, these valves close. I denominate them safety-valves," as in giving relief as described they prevent bursting or starting cf the cylinder heads, or otherwise producing break.- age or damage.

What I claim as my invention, and desire to secure by Letters Patent, is*

r i.he combination with the valve-box D, arranged within the steam-chest, of the valves N1 N2, controlling openings in communication with the steam-ports, essentially as and for the purpose herein set forth.

G. H. HOAGLAND.

Witnesses;

I. W. Coe-Mns, G.. 'd'. Item. 

